Educational appliance for arithmetic



lUNITED s'rn'rlzs JOS Kncxnrs, or PORTLAND, OREGON.

EDUCATIONAL APPLIANGE FOR ARITHMETIC.

Application filed April 14,

To all whom t may concer/n Be it known that I, Jos Knoxnis, citizen ofthe United States, residing at Portland, in the county of Multnomah Aand State of Oregon, have invented, a new and useful Educational Appliance for Arithmetic, vof which the following is a specification.

My invention relatesV to improvements in educational appliances for arithmetic, in which a marble falls through openings in a concave vdish and finally rcomes to rest on some numeral, the factors of which are visible, while the product as represented by said numerals remains invisible until the marble is removed.

The objects of my invention are to furnish an inexpensive device which, under the guise of a fascinating game, develops the mathematical faculties of children.

Other objects and advantages are to be found in the general arrangement and the details of construction, as will be explained hereafter.

I attain these objects with the mechanism illustrated in the accompanying drawing, in which- Y Figure I is a plan view of the entire apparatus, part of the top being removed to show the construction underneath.

Fig. II is an elevation of Fig. I, the left half thereof being shown in section.

Similar numerals refer to similar parts throughout the several views.

Since multiplication is the subject which presents the most ditculty to the child, the details of construction shown in the drawing refer particularly to this branch of study. but the same device with very slight alterations can equally well be used to teach addition, subtraction and division, as will be described below.

A circular base of wood a has the upper surface sloping from the center toward the periphery. Projecting upwardly at the periphery is the rim b. Radiating from the post c at the center of the base, and resting on said base, are the walls d which divide the space around the post into eight compartments corresponding with the multipliers from 2 to 9 in a multiplication table. The multiplier l does not require extensive memorizing and is therefore omitted. A cylindrical wall e closes said compartments Y at the periphery. It should, however, be

noted that this wall e does not extend down specification of Letters Patent. Patented May 17, 1921,

v1920. serial No. 373,697.

tothe base, but leaves clearance venough vs o that a marble can pass through unhindered. Themultiplicands from 2 to 9 for each compartment are printed on the lowerv outside edge of the cylindrical wall, while the multiplier is yprinted above the multiplicands.

lFinally the compartments are covered by a concave dish f whose openings g permit a lmarble to fall intoy the respective compartment underneath. Thev upwardly extending rim z, at thepe'riphery of the concave'dish prevents ,a marble from leaving the dish, and the concave hub z' at the center of the 4dish may be utilized as a storage place for such marbles as are not needed in they game. 'The'play is conducted as follows: One or moreV children take their places at the apparatus. A` marble is thrown tangentially into l the dish, where it will circulate till it drops through one of the openings into the compartment, say 7 below. Rolling down the inclined surface of the base board, said marble will perhaps emerge at a point where the multiplicand 2 is printed at the edge of the cylindrical wall. Once emerged at this point, the marble passes between the pins y' into a groove k, at the end of which the numeral 14, as the product of 7 times 2, is printed or stamped. The factors being plainly visible all the time, the child is called upon to announce the product before it is permitted to remove the marbleand to verify its computation with the numeral underneath. A prize may reward the best-performer.

Y Addition can be practised in the same way except that thin strips of metal with the correct sums stated thereon should be used tocover the numerals which present products in the multiplication table.v It is a simple matter to corrugate the strips in conformity with the grooves in the edge of the v plurality of numbered grooves radiating toward the circumference, a post in the center ofthe base, a concave dish supported on the post, a plurality'of apertures in the dish around the post, and a plurality of numerals segregated into series on the periphery of thc concave dish, the individual numbers in Vthe series indicating an individual groove in said base and bearing a denite arithmetical relation to the number in the groove.

2. An educational-appliance, comprising a circular base having a sloping upper surface and an upwardly extending rim at the circumference, sectoral compartments radiating from the center toward the edge, a space between the lower edge of the peripheral wall of said compartments and the base to permit the passage of a marble, a concave dish covering the top of said compartments jland openings in the bottom of said concave `dish to permit a marble circulating in said dish to enter non-selectively one of the compartments below said dish.

An educational appliance, comprising a circular base having a sloping upper surface, corrugations in the upper surface near the edge, an upwardly extending rim around the circumference vof said base, compartment walls radiating from the post toward the edge, a peripheral wall connecting the Aupper portions of said compartment walls, a plurality of pins in spaced relation dividing the open portion between base and peripheral wall into equal parts, a concave dish resting on the post and compartment wallshaving an upwardly extending rim at the circumference and having openings in the bottom yol. said dish communicating with the compartments underneath, whereby a marble may enter one compartment and proceed through the pins to the rim at the base.

Signed by me at Portland, Oregon, this 8th day of April, 1920.,

JOS KEoKEis. 

